Sequential ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) scan findings in patients with extrapulmonary tuberculosis during the course of treatment—a prospective observational study

• Main Authors: Jamshed Bomanji, Rajnish Sharma, Bhagwant R. Mittal, Sanjay Gambhir, Ahmad Qureshy, Shamim M.F. Begum, Diana Paez, Mike Sathekge, Mariza Vorster, Dragana Sobic Saranovic, Pawana Pusuwan, Vera Mann, Sobhan Vinjamuri, Alimuddin Zumla, Thomas N.B. Pascual
• Other Authors: Klinicki Centar Srbije
• Format: Article
• Published: 2020
• Subjects: Medicine
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/58339
• Institution: Mahidol University

© 2020, Springer-Verlag GmbH Germany, part of Springer Nature. Background: Initial studies of tuberculosis (TB) in macaques and humans using 18F-FDG positron emission tomography (PET) imaging as a research tool suggest its usefulness in localising disease sites and as a clinical biomarker. Sequential serial scans in patients with extrapulmonary TB (EPTB) could inform on the value of PET-CT for monitoring response to treatment and defining cure. Patients and methods: HIV-negative adults with EPTB from eight sites across six countries had three 18F-FDG PET/CT scans: (i) within 2 weeks of enrolment, (ii) at 2 months into TB treatment and (iii) at end of ATT treatment. Scanning was performed according to the EANM guidelines. 18F-FDG PET/CT scans were performed 60 ± 10 min after intravenous injection of 2.5–5.0 MBq/kg of 18F-FDG. Findings: One hundred and forty-seven patients with EPTB underwent 3 sequential scans. A progressive reduction over time of both the number of active sites and the uptake level (SUVmax) at these sites was seen. At the end of WHO recommended treatment, 53/147 (36.0%) patients had negative PET/CT scans, and 94/147 (63.9%) patients remained PET/CT positive, of which 12 patients had developed MDR TB. One died of brain tuberculoma. Interpretation: Current 18F-FDG PET/CT imaging technology cannot be used clinically as a biomarker of treatment response, cure or for decision-making on when to stop EPTB treatment. PET/CT remains a research tool for TB and further development of PET/CT is required using new Mycobacterium tuberculosis-specific radiopharmaceuticals targeting high-density surface epitopes, gene targets or metabolic pathways.